Kinetics and mechanism for reduction of trans-dichloro-tetracyanoplatinate(IV) by tetraammineplatinum(II) and bis(ethylenediamine)platinum(II)
作者:Tiesheng Shi、Lars I. Elding
DOI:10.1016/s0020-1693(98)00199-6
日期:1998.11
of k(1), together with the rapid-scan spectra, implies that reduction of trans-[Pt(CN)(4)Cl-2](2-) by these Pt(II) complexes takes place directly via chloride-bridged transition states of the type [H2O ... Pt-II... Cl ... Pt-IV... Cl](not equal) for the k(1) pathway, or [Cl ... Pt-II... Cl ... Pt-IV... Cl](not equal) for the k(2) path. The higher-reaction rate of [Pt(en)(2)](2+) compared with [Pt(NH3)(4)](2+)
研究了[Pt(NH3)(4)](2+)和[Pt(en)(2)](2+)对反式[Pt(CN)(4)Cl-2](2-)的还原使用停止流分光光度法在25摄氏度下在0小于或等于[Cl-]小于或等于0.4 M的范围内。化学计量比[Pt(IV)]:[Pt(II)]为1:1。快速扫描光谱显示出清晰的等渗点,表明没有任何反应中间体积累到显着量。对于具有过量Pt(II)的伪一阶条件,观察到的速率常数可以表示为k(obsd)=(k(1)+ k(2)K [Cl-])[Pt(II)],其中k(1)= 400 +/- 10和(3.3 +/- 0.4)x10(3)M(-1)s(-1),k(2)K =(3.25 +/- 0.04)X 10( 4)和(6.67 +/- 0.07)x 10(5)M-2 s(-1)在25摄氏度下通过[Pt(NH3)(4)](2+)和[Pt(en)( 2)](2+)。该机制涉及两个平行的反应途